Researchers studying amethyst geode formation in Brazil’s lava flows have proposed temperatures below 100 °C. The new study uses similar techniques and includes an additional oxygen isotope.

The researchers discovered that the amethyst geodes formed at unexpectedly low crystallisation temperatures of just 15 to 60 ° ... Along with Ametista do Sul in southern Brazil, ...

The giant geode originally from Uruguay was shipped to Australia through Brazil in 2007. The 2.5 tons Empress of Uruguay is slightly less impressive after a tourist pinched a piece of the world's ...

Amethyst geode brings purple hue to geology gallery. A 660 kg, one-metre high geode containing amethyst crystals and sourced from solidified volcanic ash in Minas Gerais state of Brazil, ...

Amethyst geodes, in particular, contain violet quartz crystals, prized for centuries for their beauty and value. These rare formations are often found in volcanic regions, such as Uruguay or Brazil, ...

A 26,000-pound amethyst geode would not be without precedent, either: According to the Guinness Book of World Records, the largest amethyst geode (just shy of 10 feet tall) weighs 28,660 pounds.

Geodes are hollow rock filled with dazzling crystals. I'm at the American Museum of Natural History in New York City and behind me is an amethyst geode that was formed millions of years ago.

Amethyst is a violet variety of quartz that has been used as a gemstone for many centuries and is a key economic resource in northern Uruguay. Geodes are hollow rock formations often with quartz ...